1. Field of the Invention
The present invention relates to a cleaning apparatus used in an image forming apparatus such as a copying machine and a printer which use an electrophotographic process or an electrostatic recording process.
2. Description of the Related Art
A cleaning blade provided in the cleaning apparatus for cleaning an image bearing member such as a photosensitive drum and an intermediate transfer member is regarded as a consumable and replaced with a new one when it reaches its life time. The cleaning blade is generally replaced after the cleaning apparatus detachably mounted on a main body of the image forming apparatus has been removed from the main body thereof. When the cleaning apparatus is removed from the main body of the image forming apparatus, however, toner is liable to fall from an opening of the cleaning apparatus to dirty the inside of the image forming apparatus, and may adversely affect a product. Mounting and demounting the cleaning apparatus may damage the cleaning blade and the image bearing member.
In view of the above problem, there has been discusses a configuration illustrated in FIG. 12. FIG. 12 illustrates a toner collection tray 102 which accumulates toner falling from a space between a cleaner unit 100 and an intermediate transfer belt 101 and stores it therein. The toner collection tray 102 is provided substantially under the space between the cleaner unit 100 and the intermediate transfer belt 101 to prevent the falling toner from dirtying the inside of the image forming apparatus (refer to Japanese Patent Application Laid-Open No. 2004-109799).
A detachable cleaning apparatus 70 has been discussed as illustrated in FIG. 13. When a position regulation plate 71 is set in a release position, a rotation lever 72 and a pressing plate spring 73 are brought into a free state. Accordingly, a support shaft 76 guides the cleaning apparatus with an opening 75 of a casing 74 oriented substantially upward, and the cleaning apparatus can be mounted and demounted. This configuration can prevent the toner from falling down (refer to Japanese Patent Application Laid-Open No. 09-152823).
A detachable cleaning apparatus 80 has also been discussed, as illustrated in FIG. 14. A cleaning blade 81 is rotatable around a rotating shaft 82 in an image forming apparatus capable of preventing a cleaning unit and an image bearing member from being scratched or the image bearing member from loosening during mounting and demounting the cleaning unit. The cleaning blade 81 is separated from an intermediate transfer belt 85 by a separate arm 84 which moves along with a rotation axis 83 in attaching and detaching the cleaning blade 81. This configuration allows preventing the cleaning blade and the intermediate transfer belt from being scratched or unnecessarily bending when the cleaning blade is attached and detached (refer to Japanese Patent Application Laid-Open No. 2003-122228).
In the configuration described in Japanese Patent Application Laid-Open No. 2004-109799, however, a specific collection tray needs to be provided and a space for the tray also needs to be secured.
In the configuration described in Japanese Patent Application Laid-Open No. 09-152823, the cleaning apparatus can be mounted and demounted with the opening 75 of the cleaning apparatus oriented substantially upward, so that the toner will not spill from the opening during an mounting and demounting operation. However, if the blade is brought into contact with a member to be cleaned in the case where a rotation fulcrum 76 is arranged in a position in FIG. 12, the following problem may occur. Reaction force is generated in a direction to compress the blade in a free length direction by further pressing the blade after the blade has been brought into contact with the member, so that a leading edge of the blade and the member to be cleaned may be rubbed together to be damaged or the blade may be bent.
In the configuration described in Japanese Patent Application Laid-Open No. 2003-122228, there is provided a retreating mechanism in which the cleaning blade is separated from the intermediate transfer belt in attaching and detaching the cleaning blade, however, the apparatus is complicated in configuration and has a drawback from the viewpoint of space and cost.